Device and method for individually separating a pile of sheetlike data recording media

ABSTRACT

An apparatus for singling sheetlike data carriers is proposed wherein the stack ( 30 ) to be singled is located on a rest ( 5 ) which is movable relative to a feed device ( 4 ) in clocked fashion such that individual data carriers are moved in the direction of a singling gap whose width is variable by a retaining element ( 13 ) in synchronism with the clocked motion of the rest ( 5 ). This apparatus is able to attain a high throughput even with different sheet qualities while guaranteeing high functional safety.

This invention relates to an apparatus and method for singling a stackof sheet-like data carriers.

Such apparatuses and methods are used inter alia in bank note processingmachines to deliver individual notes of a stack to a transport systemwhich conveys the notes to testing, sorting and stacking devices forfurther processing. The throughput of a bank note processor isdetermined quite crucially by the power of the singler.

EP 0 535 467 B1 discloses a singling apparatus for paper sheets whereinthe stack rests on a lifting device movable up and down between conveyerbelts. Up and down motion of the lifting device causes presinglingrolls, which are elastically biased, to be raised off or lowered ontothe conveyer belts jointly with the leading portion of the stack graspedby said rolls. The singling gap is adjusted firmly between a feed rolland a fixed singling roll, the singling roll being supposed to retainthe following sheets located on the paper sheet to be singled.

Although the known singling apparatus permits individual sheets to beremoved from a stack due to the clocked up and down motion of thelifting device, in particular with constant paper quality, andoptionally also produces gaps between individual sheets if the liftingdevice is driven accordingly, the known singling apparatus reaches itslimits at high singling speeds and/or with different sheet qualitieswhen disturbances occur, e.g. double picks or clogging of the singlinggap. Since the singling gap is adjusted to a sheet thickness, verystrong pressure in the singling gap already arises when a sheet with afolded-in leading edge is fed, which can lead to a disturbance, forexample clogging of the singling gap. But even if such a folded-in sheetpasses the singling gap, the load on said sheet is very strong so thatthe sheet can be damaged, e.g. dog-ears torn off or the like.

The invention is therefore based on the problem of providing anapparatus for singling sheetlike data carriers which also works withdifferent sheet qualities of the data carriers at high throughput andwith high fictional safety. The data carriers should also be singled inan especially gentle way.

This problem is solved by the features of the main claim.

The inventive solution involves clocked interruption of the action of afeed device on the stack and, in synchronism with this process, a changein the width of the singling gap. In addition to said change of thesingling gap, the retaining force on the next data carrier to be singledis influenced. The inventive solution permits very high throughputs tobe reached without disturbances by jammed data carriers even if thestack contains data carriers of very different quality (e.g. roughness,limpness, thickness, etc.). The invention also permits the gaps betweensuccessively singled data carriers to be especially exactly adjusted andmaintained even at different lengths. Further, the retaining force onthe data carriers can be very finely adjusted, thereby achieving optimalgentleness for the data carriers.

Further advantageous features and the functioning and structure of theinvention will result from the following description of an example forsingling bank notes with reference to the drawing, in which:

FIG. 1 shows a side view of the singling apparatus,

FIGS. 2a-d show views of the singling gap in four different operatingconditions,

FIG. 3 shows a further example in a side view,

FIG. 4 shows a sectional view of the example according to FIG. 3, and

FIG. 5 shows another further example in a side view.

FIG. 1 shows a singling apparatus for bank note stacks 30 which areinserted into an input pocket not shown in detail. The short sides ofthe notes pointing in the singling direction are aligned therein withbank note stop face 3. The input pocket is limited downward by the upperrun of conveyer belt 4 and the rest executed as rocker rest 5. Rockerrest 5 is executed in the form of two strip-shaped members fastened tocommon holder 6 and each extending on one side of conveyer belt 4parallel thereto. Associated with holder 6 is rotatingly drivable camdisk 7 which controls the lifting motion of rocker rest 5.

Conveyer belt 4 extends between drive roll 8 and deflection roll 9 andis acted upon by support roll 10 roughly below bank note stop face 3.Above drive roll 8 there is first transport roll 12 of a transportsystem following the singling apparatus so that an incoming bank notecan be clamped and transported between transport roll 12 and freelyrotating rolls disposed laterally of drive roll 8.

Above the upper run of conveyer belt 4, roughly between drive roll 8 andsupport roll 10, retaining device 13 is pivotally mounted around swivelaxle 14. Fastened to the lower side of retaining device 13 arealtogether four retaining runners 15 aligned with rocker rest 5 orconveyer belt 4. As indicated by FIG. 2, the two outer runners 15 areprovided above rocker rest 5 while the two middle runners 15 a arealigned with corresponding grooves 16 extending in the longitudinaldirection of belt 4. Grooves 16 and retaining runners 15 have arectangular cross section.

Altogether three pressure rolls 17 are disposed between retainingrunners 15 and the input pocket, rolling on the three conveyer beltportions located beside the two grooves 16. Guide strips 18 extendbetween pressure rolls 17 and laterally thereof, being formed asextensions of bank note stop face 3 connected with retaining device 13.The guide strips extend at an angle of about 45° to stop face 3 or areprovided with a corresponding radius, their ends facing conveyer belt 4being aligned in the direction of retaining runners 15.

Pressure rolls 17 are fastened to a common rotation axle mounted so asto be freely rotatable and vertically displaceable in an oblong hole inretaining device 13.

The retaining device is supported on rocker rest 5 by reason of its ownweight and/or a biasing element as shown by arrow 13 b. Alternatively, adirect coupling of retaining device 13 and rocker rest 5 is alsopossible. The swivel motion directed toward conveyer belt 4 is limitedby stop 19 which can be adjusted by adjusting wheel 20 and shackle 13 aof retaining device 13 and thus adapted to note quality. Adjusting wheel20 protrudes through a window in note stop face 3 so that it is alwaysaccessible without any great effort. To permit adjustment orreadjustment of the position of runners 15 in the vertical directionthey can be acted upon by adjusting screw 21.

Indicated by double arrow 31 and the broken-line view of rocker rest 5,FIG. 1 shows the lifting motion of rest 5. The rest is shifted duringlifting motion such that bank note stack 30 is lifted off belt 4 firstwith the end facing away from the retaining device and redeposited onbelt 4 first with the end facing the retaining device. This ensures thatthe lowermost sheet is always pulled and not pushed. This can be doneeither by a swivel motion of rest 5, as shown, or by a strict liftingmotion, rest 5 being aligned at an angle of a few degrees relative tothe upper run of belt 4.

In both cases the motion of rocker rest 5 raises or lowers the retainingdevice resting on rest 5 at clamping point 32 via the two outerretaining runners 15. Retaining device 13 is thereby swiveled aroundswivel axle 14, which also produces by means of bank note stop face 3 ashaking motion having a positive effect on the alignment of the banknotes.

The mode of functioning of the singling apparatus will be explained moreclosely in the following with reference to FIG. 2, FIG. 2a showing thephase in which rocker rest 5 is maximally lifted off conveyer belt 4.The singling gap, formed by retaining runners 15 a and correspondinggrooves 16 of conveyer belt 4, is maximally opened at this time and theclamping force at clamping points 32 between retaining runners 15 androcker rest 5 is maximal. This singling phase corresponds to theposition of the rocker rest in the dashed view of FIG. 1.

Bank note stack 30 is lifted off conveyer belt 4 at this time, andbetween the upper side of conveyer belt 4 and the lower edge ofretaining runners 15 a there is gap 33 of about one bank note thickness,i.e. about 0.1 to 0.2 mm. From this position rocker rest 5 is nowlowered so that first, as shown in FIG. 2b, the lower side of retainingrunners 15 a and the surface of conveyer belt 4 are located on a commonplane, i.e. the singling gap is closed, but there is not yet any meshingbetween conveyer belt and retaining runners. Distance 33 thuscorresponds to 0 mm and at clamping point 32 there is contact betweenrunners 15 and rest 5 but no appreciable clamping forces arise atclamping point 32 due to the elasticity of rest 5. The lowering ofrocker rest 5 into the middle position causes lowermost bank note BN ofstack 30 to come in contact with permanently circulating conveyer belt 4and move in the direction of the singling gap. The note can be pushedinto the singling gap despite retaining runners 15 resting on rockerrest 5 due to the action of conveyer belt 4 since the retaining runnershave an aperture angle relative to the upper run of conveyer belt 4 androcker rest 5. The next bank note is drawn along a piece due to thefriction between the two bank notes, but retained by runners 15, 15 a.

FIG. 2c shows the operating condition in which rocker rest 5 is loweredmaximally and retaining device 13 lies against stop 19 so that a freegap arises between the rocker rest and retaining runners 15. At thistime the two inner retaining runners 15 a have already moved into groove16 of conveyer belt 4; this meshing 34 is somewhat more than one banknote thickness, i.e. about 0.2 mm.

At this time the next bank note is standing with its leading edge at thesingling gap, i.e. at retaining runners 15; the lowermost note alreadylocated in the singling gap is moved further by conveyer belt 4 until itis grasped by transport roll 12 which is then available for furthertransport.

Rocker rest 5 is raised out of this position again, the next note islifted off conveyer belt 4, thereby preventing pushing from behind inthe direction of the singling gap which would be undesirable at thistime. While rocker rest 5 is lifted in the upward direction through themiddle position shown in FIG. 2d, which corresponds to view 2 b again,until it reaches a position according to FIG. 2a, the trailing end offirst bank note BN to be singled is still located in the singling gap sothat it is increasingly loaded by the clamping force between rocker rest5 and retaining runners 15, but is pulled out of the singling gap by thefollowing transport system. This causes tensile forces to be applied tosaid bank note, which smooth it. Simultaneously, this clamping atclamping point 32, which has its maximum value at this time, causes thenext bank note to be singled to be retained at the singling gap. Thisproduces a desired gap between two bank notes.

From the position shown in FIG. 2a the method shown above is nowrepeated so that the second bank note is transported into the singlinggap while the third bank note is held back and at a distance, asdescribed above.

During this process, pressure roll 17 rotating through the bank notemotion together with guide strips 18 causes individual notes to fan outand the note to be singled to be pressed onto conveyer belt 4. Thisfunction is especially important in particular with the last note of astack, i.e. when there is no pressing force from the weight of thestack. In conjunction with guide strips 18 there is also a preprofilingof the note, which favors its feed into the singling gap (incipientmeshing).

Since the next bank note to be singled is still retained during theupward motion of rocker rest 5, it is also possible to single bank notesof different lengths out of a common stack and nevertheless produce agap, whose length is then dependent on the bank note length. Theretaining of the next bank note is then caused as of the condition shownin FIG. 2d (middle position) by the now increasing clamping force atclamping point 32. This retaining effect is of course favored by thefact that the action of conveyer belt 4 is reduced during the upwardmotion of rocker rest 5.

By accordingly controlling the motion of rocker rest 5 one can directlyinfluence the length of the gap between two bank notes. If cam disk 7runs in synchronism with the conveyer belt for example, the gap is onlydependent on the length of the particular adjacent bank notes. When astack of equally long bank notes is singled, constant gaps then arise.

It is also possible to detect the trailing edge of the last singled banknote by means of corresponding sensor 2 directly behind the singlingapparatus and to drive rocker rest 5 such that equally great gaps arealways produced between the individual notes even with differently longconsecutive notes (mixed depositions).

During the singling process the frictional forces between the lowermostbank note and conveyer belt 4 must be greater than the frictional forcesbetween the first and second bank notes. In order to obtain maximumadhesion between bank note and conveyer belt, conveyer belt 4 isprovided in a further embodiment of the invention with two portionsuniformly distributed along the circumference and each having a holepattern which cooperate with suction box 11, disposed between drive roll8 and support roll 10, over which conveyer belt 4 runs and which has aconnection (not shown) with a vacuum source. Shortly after the transportof the first bank note has begun after action by conveyer belt 4, one ofthe perforated areas of the belt lies against the area of the leadingedge of the bank note and increases adhesion between belt 4 and thelowermost note during passage over suction box 11. The length of theconveyer belt or the distance between the two hole patterns is selectedsuch that two bank notes are singled during one complete circulation.

FIG. 3 shows the further embodiment and one of the two hole patternswith individual holes 40 in a position above suction box 11.

In a further embodiment of the invention as shown in FIG. 5, it isprovided that the vacuum in suction box 11 is controllable by a valveunit for example. In contrast to the above-described embodiment theconveyer belt then has no partial perforation but one distributedcontinuously over the total belt length. Connecting the vacuum thenpermits the bank note to be subjected to the vacuum for differentlengths of time coordinated with the particular bank note length. Thispermits selective control of the action of the conveyer belt on thelowermost bank note. By corresponding vacuum control in suction box 11one can also influence the gap between two consecutively singled banknotes.

A further advantage of this embodiment is that, in contrast to thepartly perforated belt where wear always takes place in the area of thehole pattern, uniform wear arises over the total circumference of thebelt, resulting in especially long service life of a conveyer belt.

The arrangement of two suction chambers, one suction chamber disposedbefore the singling gap in the transport direction and the other suctionchamber behind the singling gap, makes it possible to act upon said twosuction chambers with a time overlap, successively. The suction forcesupporting transport can thus be exerted on the bank note just beingsingled as long as possible during its motion through the narrowsingling gap, without the bank note thereabove to be singled next beinggrasped yet. In this embodiment the suction action travels a piece ofthe conveying path with the bank note, so to speak.

To increase the retaining force by retaining device 13, suction area 41can also be disposed in retaining element 13.

As shown in FIG. 4, suction area 41 is provided between the two innerretaining runners 15 a. While suction force only occurs on belt 4 whenholes 40 are running across suction box 11, suction force is permanentlyeffective on retaining element 13 since no control elements for thesuction action or interruption are provided here.

The suction action through suction area 41 in retaining element 13improves the retaining effect on the bank notes so that the clampingforces at clamping point 32 and thus the frictional stress on the banknote can be reduced. This clearly spares the bank notes during singling.

Adhesion between the bank notes to be singled and conveyer belt 4 canalso be increased by compressed air action through a pressure area (notshown) disposed after clamping point 32 in the singling direction.

What is claimed is:
 1. An apparatus having a feed device (4) forsingling sheetlike data carriers from a stack (30) positioned on a rest(5), the feed device (4) and rest (5) being movable relative to eachother in a clocked motion such that individual data carriers are movedin the direction of a singling gap having a variable width, and thewidth of the singling gap being delimited by a retaining device and thefeed device (4), wherein adjustment of the width of the singling gap isvariably synchronized with the clocked motion of the feed device and therest.
 2. An apparatus according to claim 1, characterized in that theretaining device (13) is controlled in accordance with the motion of therest (5) for changing the width of the singling gap.
 3. An apparatusaccording to claim 1, characterized in that the retaining device (13)can be acted upon directly by the rest (5).
 4. An apparatus according toclaim 1, characterized in that the retaining device (15 a) and the feeddevice (4) have profiles which mesh with each other.
 5. An apparatusaccording to claim 1, characterized in that the motion of the rest (5)is a lifting and/or swivel motion.
 6. An apparatus according to claim 5,characterized in that the swivel motion of the rest (5) is effectedaround a pivot located on the side of the singling gap opposite thestack (30).
 7. An apparatus according to claim 1, characterized in thatthe retaining device (13) has at least one clamping element (15) forproducing a normal force on the data carriers.
 8. An apparatus accordingto claim 7, characterized in that the rest (5) serves as a support forthe normal force produced by the clamping element (15) on the oppositeside of the data carrier.
 9. An apparatus according to claim 1,characterized in that the retaining device (13) is acted upon by abiasing element in the direction of the feed device (4).
 10. Anapparatus according to claim 1, characterized in that the rest (5) isinclined toward the singling gap relative to the conveying direction ofthe feed device (4).
 11. An apparatus according to claim 1,characterized in that the feed device (4) is provided with at least onesuction area for subjecting the adjacent data carrier to a vacuum. 12.An apparatus according to claim 11, characterized in that the feeddevice (4) is a conveyer belt partly provided with at least one holepattern.
 13. An apparatus according to claim 11, characterized in thatthe feed device is a conveyer belt with a perforation extending over thetotal belt length and the conveyer belt cooperates with a suctionchamber (11) whose vacuum is controllable.
 14. An apparatus according toclaim 13, characterized in that the suction area comprises two suctionchambers (11), the vacuum of each suction chamber being controllable.15. An apparatus according to claim 14, characterized in that onesuction chamber is provided before the singling gap in the transportdirection and the other suction chamber therebehind.
 16. An apparatusaccording to claim 1, characterized in that the retaining device (13)has a pressure roll (17) preceding the singling gap.
 17. An apparatusaccording to claim 1, characterized in that the retaining device (13)has a suction area (41) for acting upon the adjacent data carrier. 18.An apparatus according to claim 1, characterized in that a sensor (2) isprovided after the singling gap in the singling direction for detectingthe distance between two singled data carriers, its output signal beingused to maintain predetermined distances of the control of the singlingapparatus.
 19. A method for singling sheetlike data carriers from astack (30) located on a rest (5) with a feed device (4), wherein thefeed device (4) and rest (5) are movable relative to each other inclocked fashion such that individual data carriers are moved in thedirection of a singling gap limited by a retaining device and the feeddevice (4), and wherein in a first step a) the stack (30) is depositedon the rest (5), characterized by the following further method steps: b)moving the rest (5) and a feed device (4) toward each other so that thedata carrier acted upon directly by the feed device (4) is moved atleast partly through the singling gap limited by the retaining device(13) and the feed device (4), simultaneously closing the singling gap sothat the next data carrier is retained at the singling gap, c) movingthe rest (5) and feed device (4) apart and ending or at least reducingthe action of the feed device (4) on the stack (30) and opening thesingling gap, d) repeating steps b) and c).
 20. A method according toclaim 19, characterized in that the data carrier is acted upon by aretaining force at the time when the moving apart of rest (5) and feeddevice (4) is ended.
 21. A method according to claim 20, characterizedin that the retaining force is continuously adjusted.